


Power Ratio

by MiyuKazu



Category: Haikyuu!!
Genre: C'mon, F/M, Humor, Lots of plot, OC is a powerlifter, Plot, Romance, Strong Independent Woman Who Don't Need No Oikawa, Teen Romance, Tooru is literally so annoying, cursing, honestly, mildly offensive language, she's just trying to have a good time, someone please help her, they're teenaged athletes, why is he like this
Language: English
Status: In-Progress
Published: 2017-11-22
Updated: 2017-11-30
Packaged: 2019-02-05 18:17:31
Rating: Teen And Up Audiences
Warnings: Creator Chose Not To Use Archive Warnings, No Archive Warnings Apply
Chapters: 3
Words: 3,404
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/12799689
Author URL: https://archiveofourown.org/users/MiyuKazu/pseuds/MiyuKazu
Summary: She was just trying to work out in peace. Really. Some people just like to make her life so difficult.





	1. Literally Why

**Author's Note:**

> A/N: Hello, here is my new Haikyuu story! I honestly do not have the right amount of commitment to be publishing another story, but I don't care. The plot bunnies wouldn't go away. By the way, I do have somewhat of a plot to this story. Chapters may or may not end up being posted chronologically though.

**Summary for the Chapter:**

> She totally did a thousand years of pain on him.

Seiko's grip on the bar tightened. She clenched her teeth and let out a slow hissing sound as she flexed her thighs and core. Slowly but surely, she was lifting the weight of the bar up. Of course, this weight was nothing compared to what she could do the previous year. It was nothing compared to the weight that earned her the title of State Champion back when she was still competing for her high school back in America.

But, well. What could she do about it other than man up and show the bar who's boss? After all, it was her own fault that she had trained so hard the last year that she had destroyed both her knee and any hope of her reclaiming her title. It was a miracle that she was even able to lift at all, but Seiko was known for being especially stubborn once motivated.

And boy, was she motivated. She _would_ surpass her previous maxes. Fuck what those doctors said. And competing in Japan may be much different than competing in the States, but mama didn't raise no _bitch_ , and Hara Seiko will absolutely not back down until she has finished conquering Japan.

She _will_ conquer Japan. Just. Just let her finish squatting this weight first.

Faintly, Seiko could hear the voices of her older brother and other teammates screaming at her. While she did appreciate the sentiment, she really couldn't hear them over her loud, loud heart. She grinned at her reflection in the mirror as a very familiar wave of adrenaline washed over her body.

" _Up_ , Seiko! _UP_!"

"C'mon, big girl! You can do it!"

"I CAN SQUAT THIS MUCH IN MY _SLEEP_ , SEIKO!"

" _BREATHE_ , BIG GIRL! YOU'RE ALMOST THERE!"

"UP! _UP_! **_UP_**!"

And just as Seiko was about to conquer the daunting weight of two-hundred and thirty pounds, the weight room door slammed open and in came the volleyball boys for their daily dose of weight training.

As if their sudden intrusion hadn't surprised her enough, a very loud, very obnoxious voice in the back shouted;

"IWA-CHAN! _LOOK_! SEI-CHAN IS _SO STRONG_!"

Startled out of her mind, Seiko dropped the heavy weight onto the safety bars and fell to the ground, bumping her forehead against a safety bar in the process. In perfect tandem, Seijou High's entire powerlifting team turned to the source of the obnoxious voice and glared.

"OIKAWA TOORU." Seiko growled from her spot on the floor, "I WILL _ACTUALLY KILL_ YOU!"

The powerlifting team didn't even try to stop her as she unstrapped her training belt from her waist and bolted after her fellow second year. In fact, the captain of the volleyball team was looking mighty uncomfortable, sandwiched between a wall and the intimidating form of the powerlifting team captain, Hara Yukio.

"You volleyball guys sure have impeccable timing," Yukio sniffed, emitting a dark aura around him as he raised his large hand into the air.

"FIVE. TIMES." The volleyball captain flinched, fearing that Yukio might slap him when he shook his hand for emphasis, "Five times this week, you have interrupted our practice. _Five. Times_. You have interrupted while someone was maxing out. Do you have some kind of superpower? Do you hate us or something? How were you so accurately able to interrupt us like this? FIVE. TIMES?"

Before the poor volleyball captain could even defend himself; the powerlifting team's vice-captain, a spitfire who answered to the name Ishikawa Atsushi, grabbed him by the caller of his jersey, lifted him off the floor, and shook him. "HOW MANY TIMES DO I NEEDA TEACH YA TA ENTER THE WEIGHT ROOM QUIETLY, HAAAH?"

Members of the volleyball team paled as other members of the powerlifting team began emitting the same dark aura as Yukio.

"I'm sorry," the volleyball captain squeaked, "It won't happen again!"

"That's what you said last time." Yukio sneered whilst Atsushi simultaneously shouted, "SWEAR ON YOUR MANHOOD THAT THIS WON'T HAPPEN AGAIN!"

" _I swear_!"

Atsushi was just about to retaliate when an ominous scream coming from outside the weight room filled the space. Moments later, Seiko dragged in a teary eyed setter.

"Oikawa-kun's going to be a good boy who only uses his inside voice in the weight room from now on, isn't he?"

The poor boy could only let out a whimper.

* * *

 

"SEIII-CHAAAAAN!"

Seiko immediately sighed and rubbed at her temples, already missing the peaceful lunch that she was having just seconds prior.

Fortunately, Oikawa Tooru did not share the same home room as her. _Unfortunately_ , Hanamaki and Matsukawa, both of whom she was quite fond of, did. And that gave Tooru a very nice excuse to use when he wanted to hop into their class and annoy Seiko. Hajime popped his head out into view from behind his much louder friend, waving at the already eating trio before following after Tooru towards them.

As soon as the setter sat down, he began to chopstick-battle with Seiko for parts of her lunch.

"No, Shittykawa! You have your own food!" She elbowed him before leaning over her desk and shoveling as much food as she could into her mouth.

"Aww! Sei-chan, please! My mom doesn't cook as well as Yukio-senpai!"

"No, I don't care!"

The other three volleyball players watched for a while, amused, while they indulged in their own lunches. "Oh yeah," Hanamaki suddenly pointed at Seiko with his chopsticks, "What exactly did you do to the King this morning anyway?"

At that, Oikawa suddenly paled.

"Hanamaki, if you love me, you will never ask of that again."

Seiko let out an eerie laugh.

"Ooooo~" Hanamaki leaned in closer, "Now I _really_ want to know."

Matsukawa and Hajime exchanged quick glances before shrugging and leaning in as well, also wanting to know this deep, dark secret.

"Oh," Seiko contemplated as she chewed, "I think I'll keep that a secret for now."

Hanamaki raised an eyebrow.

"If I tell you, you guys will do it to him too. Then he'll get used to it and I won't be able to control him anymore." She grinned, "Besides, isn't it more fun if nobody else knows?" She giggled deviously.

**Notes for the Chapter:**

> A/N: Fun fact, I am actually a powerlifter irl. I'm currently a junior in high school and I placed fifth at the state championships my freshman year and seventh my sophomore year. When I speak for Seiko, I do speak through many personal experiences. Seiko is absolutely not based after myself though! She's way cooler and stronger than me.
> 
> Yukio, however, is based off of someone who's very important to me irl. At the beginning of my freshman year, I was overweight and severely depressed. I have a friend who I think of as an older brother who dragged me by the back of my shirt to the weight room as soon as powerlifting season started that year. He pushed me to work off my frustrations and pushed me to become a better person and yeah, I was extremely annoyed by him at first, but now I'm incredibly thankful. He and powerlifting both took part in shaping me into who I am today.
> 
> During my first year of powerlifting, I lost about 30 lbs and am currently no longer overweight. And though I am still depressed, I can say that having this hobby has significantly improved my mental health along with my physical health.
> 
> Anyway, here's a rundown of the OCs we've been introduced to thus far;
> 
> Hara Seiko  
> •2nd Year  
> •Ethnicity: Japanese-American  
> •Age: 16  
> •Height: 5 ft. 9  
> •Weight: 163  
> •Hair: Almost-black blue. Straight lob cut. Half of hair always in a bun.  
> •Eyes: Dark brown  
> •Skin: Pasty  
> •Desc: a snarky and mischievous girl who's just trying to have a good time. honestly.
> 
> Hara Yukio  
> •3rd Year. Captain.  
> •Ethnicity: Japanese-American  
> •Age: 18  
> •Height: 6 ft.  
> •Weight: 173  
> •Hair: Almost-black Blue. Undercut. Hair long enough to be put in a bun.  
> •Eyes: Dark brown  
> •Skin: lightly tanned  
> •Desc: a stern and dependable big brother character, who has a soft side for cute things.
> 
> Ishikawa Atsushi  
> •3rd Year. Vice Captain.  
> •Ethnicity: Japanese  
> •Age: 17  
> •Height: 5 ft. 8  
> •Weight: 134  
> •Hair: Pastel pink. Left side shaved. Chin length hair.  
> •Eyes: really, really light brown  
> •Skin: medium tanned  
> •Desc: a slave driver, basically. angry 24/7 but he's just a tsun. fearless.


	2. First Ecounter

**Summary for the Chapter:**

> Oikawa is a man with sophisticated tastes.   
> He likes his women like his chicken.  
> Thicc and with lots of ass and thighs.

They had first met towards the middle of their first year of high school. Rumors of a pair of foreign students transferring in had piqued his interest at the beginning of that week, but he'd long forgotten about the gossip by Wednesday. He had other things on his mind. Like the new Marvel movie that came out the previous night that he just _had_ to see, biology homework, English homework, pretty ladies, and bullying Iwa-chan.

It was early in the morning. Too early to even be alive, in fact, but Hajime insisted on hitting the weights even earlier than usual since Tooru had skipped the past two days, choosing instead to sleep in after staying up all night watching volleyball matches. It was a known fact that Oikawa Tooru and Iwaizumi Hajime frequented the weight room every morning before school. Of course they weren't the only ones. Other athletes from other teams joined them from time to time, but the volleyball pair were known for being consistent. They were there almost every morning regardless of weather, holidays, or how well they were feeling.

Which was exactly why they found it quite odd that there was a barely clothed girl sitting on a bench, stretching her arms. This early in the morning. On a snowy day. Even odder still, Tooru had no idea who this chick was. Tooru _never_ forgot a pretty face. And this girl was _pretty_.

Immediately after noticing her, young Tooru popped up his jacket collar and sauntered towards her, completely ignoring Iwa-chan’s protests. He leaned against a bench rack as he waited for her to notice him.

She raised an eyebrow.

“ _Hello_ there, _cutie_ ,” He stuck out a hand, “You may or may not have heard of me, but I'm Oikawa Tooru. Aobajouhsai’s volleyball star.”

He winked.

The pretty girl only blinked in response before slowly putting the earbuds hanging around her neck into her ears and turning up her music as loud as possible.

She let out a long, heavy sigh as the heavy metal blaring into her ears echoed throughout the previously silent weight room. Hajime, who'd been stretching, paused in his movements, now alarmed by the sudden sounds of heavy drumming and screaming.

“Sorry,” the girl dryly replied, “I can't hear you over my music.”

At that, Hajime couldn't help but let out a snicker.

“I- wha-” Tooru stood in front of her, gaping, as she began to bench press just the bar as a warm up. “Y-you! You weren't even listening to music when I approached you!” He sputtered.

“Hah!” Hajime chuckled as he grabbed the other boy by his jacket collar and dragged him away, “Serves you right for bothering her.”

“Iwa-chaaaan!” The setter sobbed comically, “she completely ignored me!”

“She made the right choice.”

Oikawa Tooru, resident pretty boy, was shocked. He was _never_ ignored by humans of the opposite gender. Ever. Regardless of how old or young or sexual orientation. Girls _never_ ignored him. And this girl, this pretty girl with her _stupid_ pretty blue hair and her _stupid_ pretty voice completely. Outright. Ignored him.

Throughout that morning’s weightlifting session, Tooru found himself distracted more than once. Every so often, he would glance at her and there she would be, just working out. Looking all pretty and stuff. He was upset on many different levels and intrigued, all the same.

“Hajime.” He said seriously, for once, “I think I'm in love.”

The other boy frowned, looking down at the setter as he watched him lift the bar up.

“I think you're only saying that because you know she's not interested in you. You're in it for the chase, man.”

Oikawa didn't respond. He instead focused on his breathing as he brought the heavy weight up and down. Iwaizumi caught the weight after the other boy finished his last rep and racked the bar. He continued to stare down at his friend, expectantly.

“Fuuuu~” Tooru pouted, “You're no fun, Iwa-chan!”

Hajime was right. He was only in it for the chase.

And because he found this girl very attractive.

“I'm going to get her number by the end of this week though!”

Iwaizumi rolled his eyes.

“Sure you will, ‘cause she seemed _so_ interested before, right?”

“Ahem,” both boys jolted, surprised, “If neither of you are busy, could you video my next rep for me? I need to check my form.”

She was clearly asking Hajime.

Tooru volunteered himself for the job.

“I’ll do it!” He sat up from the bench and waved his arm excitedly.

She stared, unamused.

“Only if you tell me your name though~”

The girl immediately turned around and dropped her phone into Hajime’s open palm.

“Wait, no! Just kidding!” Tooru chased after the girl and his friend, “I'll do it!! Iwa-chan, give me the phone!”

He snatched the phone out of his friend’s hand and excitedly gave the girl a thumbs up when she situated herself in a low squat position, behind a bar that was rested on the ground.

“Holy cow, Iwa-chan! That's like 75 kilos! Can she really lift that?”

“I can hear you, ya’ know,” the girl called, “and I'll show you that I can. Start the recording now.”

Tooru tapped on the red button on the screen. He watched her intently, silently motioning to Hajime to stand a little ways behind her to catch her if anything were to happen.

Very quickly, the girl snatched the bar from the ground, jumped, and flipped her arms upward, shooting her elbows out in front of her. She landed in a squat position again, this time with the bar resting on her collarbones and her elbows and shoulders supporting the weight.

Oikawa gulped.

_Holy shit._

That weight. Her ass. Her _ass_ looked _incredible_ , _oh hmy g oddd._

And those shorts??? _Spanks???_ Left almost nothing to imagination.

Slowly the girl straightened herself from her squat position and threw her arms forward, letting her thighs lessen the impact of the weight before bending over and dropping the bar. The rubber plates attached to the bar bounced slightly off the rubber mats on the floor.

Oikawa stopped the video.

“And that's how you do a _proper_ power clean, boys.” She chuckled as she replayed the video and watched her form. “My favorite lift.”

“Thanks, by the way.” She snickered as she locked her phone and shoved it into jacket her pocket.

Assuming that she meant ‘thanks for recording me,’ Tooru opened his mouth to shoot out a pickup line or two but then she smacked her own ass as she walked away and it dawned on him.

He had said that her ass looked incredible.

Out loud.

Tooru went red in mortification and Hajime was laughing so hard, he was holding onto a rack to steady himself.

He was never going to live this down.

* * *

“Class, as you all may know, we have a new student today.”

Tooru immediately perked up in interest when a familiar head of blue stepped into the classroom and bowed.

Tooru blinked. “Oi, Iwa-chan! That's-”

“Hello, everyone. My name is Hara Seiko and I'm transferring here from a high school in America.”

Her eyes made contact with his after she finished bowing, “I’m the first and only girl on Seijou’s Powerlifting team. My brother and I were scouted after we won a couple competitions back in the states at the beginning of the year. Nice to meet you.”

**Notes for the Chapter:**

> I don't feel bad about embarrassing him.  
> People like to depict him as a suave casanova but I'm under the impression that he's a big fat alien loving nerd.


	3. Seiko hangry! Seiko smash!

**Summary for the Chapter:**

> Pasta is the way to any girl's heart.

**Notes for the Chapter:**

> This takes place their first year!

Tooru let out a small squeak when a very familiar girl abruptly slid the classroom door open, slamming it into the wall in the process. It was early morning, just before school had started for the day. He exchanged nervous glances with Hajime as they watched her angrily slide the door shut before pouting, crossing her arms, and shuffling to her desk without picking up her feet.

"I can't do this anymore!" Seiko cried aloud before flopping over the desk across the row from Hajime. "I am _so_ HANGRY!" She screamed, her voice muffled by the wooden desk.

The boys blinked.

"Have you tried eating breakfast?" Tooru asked, only to be smacked in the chest by his friend.

"Do you pay attention? She's been cutting weight, Bakakawa. She's complained about it for days." Hajime rolled his eyes, "Oi," he frowned at the girl as she moped, "Eat fruits or something. They're light in calories and they burn fast."

"But, I'm tired of just fruit and lettuce and sashimi!" Seiko wailed, "I WANT BREAD! I WANT DRESSING! I want," at this, she shot up into a sitting position and clutched painfully at her chest, " _chicken alfredo_!"

The boys blinked.

"You underestimate how much I love noodles." She continued to rant, "I ate them almost every day! Noodles of every culture, of every kind. I. Love. Noodles. BUT NOW, I _CAN'T_ EAT THEM FOR LIKE TWO MONTHS!"

Hajime snorted. "This wouldn't have happened if you'd watched your weight and calorie counted while you were supposed to during the off sea-"

"SHUT THY DIRTY MOUTH, THOU _FROWARD_ _STRUMPET_ ," The girl screeched, "YOU KNOW I CAN'T TURN DOWN GOOD FOOD."

Tooru had to clamp his mouth shut with his hands to keep from laughing out loud and becoming the object of Hajime's wrath. She had seriously just called him...a _strumpet_. A _female prostitute_.

Hajime punched him anyway.

"Iwa-chan! _Why_?! _Seiko_ said it!"

"I don't hit girls, Ahokawa."

"Hit me, I dare you. I can take it."

"I am not going to hit you."

" _Scared_?"

"YEAH, IWA-CHAN. _Sca-OW_! _WHY_?!"

"Because you're shitty and I hate you."

"HAH!" Seiko pointed, "He hates you!"

Tooru stared at the offending finger. Then he gently held her wrist in his hand, slowly leaned forward…

and bit it.

"WHAT THE FUCK, KUSOKAWA."

"I detest the both of you." Hajime face palmed.

Tashijima sensei wasn't even surprised when he entered his classroom, only to be greeted by a highly amused class and complete chaos in the back corner of the classroom. Iwaizumi and Oikawa often pushed their desks together in the mornings so that they could discuss volleyball things, study together, and eat breakfast with one another after working out. Tashijima, after coming a little earlier than usual one day, learned that Hara often joined the boys. While he was glad that the boys had taken a liking to the new student, the scene before him left him slightly exasperated.

Tooru was laying on his back, across the conjoined desks. Seiko was straddling him and had her fingers jabbed into his sides. Hajime leaned over him. He stood opposite of Seiko, and was restraining the setter's arms.

Tooru was basically screeching with laughter and Hajime was having a good laugh himself. And Seiko? Let's just say that she was no longer hangry™.

There were probably videos all over snapchat at this point.

"Ahem," Tashijima sensei clearned his throat. Immediately, the laughter (well, the screeching laughter. Tashijima would give them a moment to relearn how to breathe) ceased.

"Seiko-kun, please return to your desk. Oikawa-kun, Iwaizumi-kun, please separate your desks and get seated. The rest of you, phones away; and everyone, please take out your textbooks and turn to page 316."

* * *

 

It was the fated day. Weigh-in day. Seiko would not be allowed to participate in the next powerlifting meet if she was over her set weight. About a month prior, Seiko discovered that she had been careless, and before she knew it, had gained about 14 pounds. She had been seriously dieting and doing intense cardio workouts in an effort to lose the extra weight and then some.

A general rule for powerlifters: the lighter you weigh and the heavier you lift, the better. It was all about power ratios. Power ratios were what decided who placed where; who won and who lost. The higher the power ratio, the higher the chances of winning.

Seiko was extremely nervous. She had went to the sauna just an hour prior, peed, ran four laps around the gym, and stripped almost completely naked just to make sure she was as light as possible. Seiko knew no modesty. It was normal for members of this team to see each other bare, especially with how often they had to weigh themselves. The powerlifting team waited with anticipation and watched tensely as the numbers on the scale continued to go up.

70...71..72...

73...73.1...74...

73.9...73.8 kilos.

163 pounds.

That was under 165. Seiko would be allowed to compete.

The team erupted into cheers, knowing how hard she'd worked to get there. Yukio roughly patted his sister's back, a knowing smile on his face. He'd also had to suffer the consequences of stress eating. Her teammates surrounded her, all with brotherly smiles on their faces and congratulations on their lips. She was both the youngest and the only female on the team. They adored her.

Seiko was brimming with excitement, hopping in place with a gigantic smile on her face.

Then, her stomach grumbled and she about fell over. Yukio caught her and tsked.

"C-can I..can I _eat_ yet?" She whimpered.

Yukio grinned.

"Don't worry, your friends are on their way.

"Friends?"

Just in time, weight room door slammed open and Oikawa Tooru marched forward, paper bag in hand. Hajime followed closely behind with a grin.

"Congrats on making weight, Sei-chan!" Tooru cheered, "Iwa-chan and I got you a present."

Seiko instantly perked up, shoved all of her beefy teammates out of the way, and basically attacked the paper bag.

She leaned on Tooru. Her bare back pressed firmly against his form. Tooru's heart raced and he had to make sure that he was still breathing properly when her bottom brushed against him. She was hanging onto his arm with one hand, and was using the other to move the contents of the bag around and peer inside.

"Oh. My god." She squealed, "You got me _chicken alfredo_?"

She turned around and threw her arms around his neck, "Oikawa Tooru, I could _kiss_ you right now!"

Hajime snickered in the background, knowing full well that Tooru had a big fat crush, even if he didn't know it yet. Tooru stood still, not really sure where he was allowed to touch her. He was also trying keep his brain from melting out of his ears.

**Notes for the Chapter:**

> This chapter was written purely only because I want Chicken Alfredo so bad and I haven't had noodles in so long and I love noodles so much and I'm trying to make weight and it's killing me because I went from eating about 3200 calories a day to 900-1600 and I'm constantly hungry and I just trying to have a good time.


End file.
